Muffler



E. J. 'MORDT MUFFLER Filed sept. 26, 1935 INVENTOR. TM rif ATTORNFY.

Patented Mar. 9, 1937 UNITED STATE PATENT OFFICE 6 Claims.

This invention relates particularly to mufiiers or devices for silencing or reducing the noise of exhaust gases from internal combustion engines or other engines and also eliminating or reducing back pressure on the engine. It may also be useful in connection with cooling or condensing other gases or for any other purpose for which it may be applicable.

The principal object of this invention is to 10 provide an improved muiiler for exhaust gases which will be simple in construction and economical to manufacture and which Will be particularly elcient in reducing or silencing the noises of the exhaust and also reducing or eliminating l5 back pressure.

Other objects are to provide a muffler having an exhaust chamber which increases gradually in size from the intake to an intermediate point and then decreases toward the exhaust outlet;

to provide a muiiler which conducts the gases around a substantially circular or spiral path providing for gradual expansion from the intake to its area of largest cross section and a gradual contraction to the outlet; to provide a muliier having passageways for conducting the gases in separate streams therethrough, said passageways being of varying length and serving to commingle the gases adjacent to the exhaust or outlet; to provide a casing of generally circular or spiral form with tangential inlet and outlet; to provide means for expanding and cooling exhaust gases from internal combustion engines, and discharging same into the atmosphere in a constant stream instead of the intermittent discharges sent out by each cylinder; to provide means for cooling the exhaust gases; and to provide such other advantages in construction and operation as will appear more fully from the following description.

In the accompanying drawing.

Figure 1 is a plan view with parts broken away to show the interior construction;

Figure 2 is a side View also with parts broken away or shown in section;

Figure 3 is a sectional view taken on line 3 3 of Figure 1;

Figure 4 is a detail of one of the partitions shown in at or extended position; and

Figures 5 and 6 are details of the partitions.

In the particular form of the invention as shown in the drawing, I provide a shell or casing I of substantially circular or spiral form, having a gradually increasing cross section from the intake toward its widest section and then 55 gradually reducing to the exhaust or outlet.

This casing has complementary top and bottom plates 8 and 9 which are provided respectively with inwardly extending peripheral flanges II) and II which form a substantially circular outer wall. These plates may be joined around the outer periphery in any suitable manner as by means of a U-shaped binding strip I2 which ts over the outwardly projecting edges of the side walls as shown particularly in Figures l and 2. This binding strip preferably ts tightly over such edges and may be welded or otherwise secured thereto in any well known manner as by means of bolts or rivets (not shown).

The top and bottom or cover plates 8 and 9 are also provided with inwardly extending flanges I3 and I4 respectively which form an inner peripheral wall and the edges of these flanges may also be joined together by means of a U-shaped strip I5 or in any other suitable manner. The shape of the plates and positions of the iianges are such that the inner peripheral wall is positioned eccentrically with respect to the outer wall.

The casing is preferably shaped so that the portions having the smallest cross section are in overlapping or offset relation as shown in Figure 2, which permits the intake and outlet pipe to be positioned in the same plane. The inlet end I6 of the casing is connected with an inlet pipe I'I, which may comprise the exhaust pipe from the engine, by means of a reducer or tapered section I8. The outlet end I9 of the casing is connected with an outlet or exhaust pipe 20 by means of a similar reducer 2|. The width of the outer iianges Ill and II also preferably increase from the inlet gradually to about the center of the casing and then decrease toward the outlet, the arrangement being such that the casing provides an exhaust chamber in which the gases may pass from the exhaust pipe into a gradually increasing area where they are cooled and the explosive force of the same will be gradually reduced and may then ow out through the outlet pipe or exhaust opening with lessened noise or silenced to a considerable extent.

However, in order to increase the silencing effeet I provide a plurality of separators or partitions 22 which extend between the top and the bottom walls and divide the casing into a plurality of ducts or passageways. These partitions preferably extend from points adjacent to the inlet opening around to points adjacent to the outlet opening and are circular in form and each partition is mounted eccentrically with respect to the center wall I5 and with respect to each other and the outer wall so that each duct or passageway increases in cross section from the inlet end to the point of largest cross section and then gradually decreases toward the outlet. It will also be noted that the inner duct or passageway is shorter in length than. the next succeeding passageway and the lengths gradually increase to the outermost passageway as shown in Figure 1.

The dividing walls or partitions 22 may be seciued to the casing in any convenient manner but I prefer to provide each partition with flanges 23 which engage with the inner surfaces of the top and bottom plates 8 and 9 of the casing, and have a plurality of tangs or prongs 24 which project through slots or holes 25 in thewalls of the casing and t closely therein. These tangs are preferably made in pairs so that the adjacent ones may be folded in opposite directions to hold the parts closely together. This fastening arrangement not only holds the partitions in position but also strengthens the walls of the casing so that they are not apt to be blown out by backre or explosions in the muirler. Y

The partitions 22 may be provided with vertical slots 26 having the metal at the far edge of each slo-t pressed inwardly to form louvers, and so as to slice off or deflect a small part of gas stream as it passes by, thereby Yreducing pressure in the corresponding channel and sending the excess gas into the next channel ahead ofthe incoming gases forming part of the same cylinder discharge in the next adjacent outer channelor duct.

From this description it will be seen that I provide a muler or device of the vtype indicated which may be made by simple operations and which will be particularly durable in-o-peration. This is in part due to the continuous passageways which prevent the accumulation of moisture and consequently prevent rusting. It is believed that the eiiiciency of the muilier will be readily apparent to those familiar with this art. It provides a plurality of substantially circular, helicoidal or volute passageways of varying length which divide the exhaust gases and let them expand and cool gradually and nally again commingle and flow out from the exhaust with little or no noise. Regardless of the theory as to the cause for the silencing eifect, I have found that in actual Vpractice my improved muffler is highly eiicient and tends to silence the exhaust to a maximum degree and also prevents back pressure on the engine, and provides quicker acceleration, thus tending to increase the eiiciency of the engine when used in. place of common forms of mufflers such as now used, which tend to cause such back pressure. In tins manner I have found that increased mileageis obtained for a given amount of fuel over that obtained with the use of other mufers now in common use. While I have shown and described a preferred form of my invention, it is apparent that modications may be made in the same to adaptit forY Vdiiicerent cars or vehicles,` or for boats, orvother uses, and therefore I do not wish to be limited to' the particular construction shown and described except as speciied in the following claims, in Which I claim. v

1. A muffler of the character set forth comprising a spiral shaped casing having a plurality of partitions providing passageways which increase from the intake to its widest point and gradually decrease to the outlet, whereby the exhaust gases are divided into different streams and are con- `ducted around substantially circular paths before passing to the atmosphere, said inlet and outlet being tangential and in the saine vertical plane.

2. A device of the character set forth, comprising a substantially spiral casing having a circular outer wall and a circular inner Wall which is eccentric thereto and which increases in cross section from the inlet to approximately the middle or to any given point and then decreases in cross section to the outlet, and a plurality of partitions in said casing which divide the same into passageways which increase in length from the center passageway to the outer passageway.

3. A device of the character set forth, including a shell of substantially spiral form, having an inlet and on outlet, the sectional area of the shell increasing from the inlet to approximately the middle or any given point and decreasing in sectional area from this point to the outlet, and having a plurality oit-transverse partitions extending from the inlet approximately to the outlet and dividing the shell into passageways of varying lenhs which increase in cross area from the inlet toward their centers and then decrease in cross area toward the outlet.

4. A muffler comprising a shell having a substantially circular outer wall and a substantially circular inner wall which is arranged eccentrically With respect to the outer wall, thus making the shell of less width at one point than at other points, the narrower portions providing inlet and outlet openings, and a plurality oi partitions in the shell arranged eccentrically with respect to the inner wall and with'respect to each other and dividing the shell into a plurality of passagewaysV of varying cross section and of different lengths.

5. A muiiler construction comprising substantially circular top and bottom plates having coe acting peripheral flanges formingA an outer wall, means for connecting said anges together, said plates also having oppositely disposed inner flanges around a central opening which is eccentric to the outer wall, means for securing the center iianges together, said plates terminating at approximately the point of narrowest width and /being offset to provide inlet and outlet orifices, a plurality of substantially circular partitions extending from points adjacent the inlet to approximately the outlet or" the casing, means for securing said partitions to the plates, an inlet pipe connected with the inlet orice, and an outlet pipe leading from the outlet orifice.

6. A muiler for explosive engines comprising a substantially circular casing provided with an inlet and an outlet and having a plurality of chambers extending from the inlet to the outlet, said chambers being eccentrically arranged with respect to the casing whereby each of the chambers increases in size from the inlet to a point about midway between the inlet and outlet and then decreases in size to the outlet, the arrangement being such that the intermittent discharges of gas from the engine will be divided and pass through said chambers, being irst allowed to' ex-Y pand and thus preventing back pressure, and then being contracted and passing out of the outlet at a substantially constant pressureand in a constant stream as distinguished from the intermittent discharges from theengine,

ERIK J. MORD'I. 

